Type (without quotes) and press enter: 'copy SYSTEM
C:\WINDOWS\SYSTEM32\CONFIG\SYSTEM'
(Yes, you want to overwrite - Go ahead and do it)

Type (without quotes) and press enter: 'del SYSTEM'

Type (without quotes) and press enter: 'exit'

At boot menu, select 'Windows XP Media Center Edition'

Join domain.

Conclusion

You can also speed up the countdown timer for selecting the operating system at boot. Goto System Properties > Advanced > Startup and Recovery > Settings. Change 'Time to display list of operating systems' to something less.